Fix errors in destruction sequence of GpuVideoEncodeAccelerator::OnWillDestroyStub()

media/gpu/ipc/service/gpu_video_encode_accelerator.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_GPU_IPC_SERVICE_GPU_VIDEO_ENCODE_ACCELERATOR_H_
 #define MEDIA_GPU_IPC_SERVICE_GPU_VIDEO_ENCODE_ACCELERATOR_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 141 matching lines @@
   const scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
 
   // GPU IO thread task runner.
   const scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   // Task runner used for posting encode tasks. If
   // TryToSetupEncodeOnSeperateThread() is true, |io_task_runner_| is used,
   // otherwise |main_thread_task_runner_|.
   scoped_refptr<base::SingleThreadTaskRunner> encode_task_runner_;
 
+  base::WeakPtr<GpuVideoEncodeAccelerator> weak_this_for_encoder_worker_;
+  base::WeakPtr<GpuVideoEncodeAccelerator> weak_this_;
+
   // Weak pointer for referring back to |this| on |encoder_worker_task_runner_|.
   base::WeakPtrFactory<GpuVideoEncodeAccelerator>
       weak_this_factory_for_encoder_worker_;
 
   // Weak pointer for VideoFrames that refer back to |this| on
-  // |main_task_runner| or |io_task_runner_|.
+  // |main_task_runner| or |io_task_runner_|. |io_task_runner_| is used if and
+  // only if |filter_| is applied.
   base::WeakPtrFactory<GpuVideoEncodeAccelerator> weak_this_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuVideoEncodeAccelerator);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_GPU_IPC_SERVICE_GPU_VIDEO_ENCODE_ACCELERATOR_H_